The version of ffmpeg

[casiphia]

My ffmpeg version: 4.0 with go get:

go get github.com/3d0c/gmf
# github.com/3d0c/gmf
go-python/muagent/src/github.com/3d0c/gmf/codec.go:198:43: could not determine kind of name for C.CODEC_CAP_EXPERIMENTAL

ffmpeg version 2.6.8 with go get:

# go get github.com/3d0c/gmf
# github.com/3d0c/gmf
../muagent/src/github.com/3d0c/gmf/codec.go:54:31: could not determine kind of name for C.FF_PROFILE_DTS_EXPRESS
../muagent/src/github.com/3d0c/gmf/codec.go:103:25: could not determine kind of name for C.FF_PROFILE_VP9_0
../muagent/src/github.com/3d0c/gmf/codec.go:104:25: could not determine kind of name for C.FF_PROFILE_VP9_1
../muagent/src/github.com/3d0c/gmf/codec.go:105:25: could not determine kind of name for C.FF_PROFILE_VP9_2
../muagent/src/github.com/3d0c/gmf/codec.go:106:25: could not determine kind of name for C.FF_PROFILE_VP9_3

So, what's the ffmpeg version is this project for?